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<table width="100%" summary="page for Bowley"><tr><td>Bowley</td><td align="right">R Documentation</td></tr></table>

<h2>
Bowley's data on values of British and Irish trade, 1855-1899
</h2>

<h3>Description</h3>


<p>In one of the first statistical textbooks, Arthur Bowley (1901)
used these data to illustrate an arithmetic and graphical analysis
of time-series data using the total value of British and Irish
exports from 1855-1899.  He presented a line graph of the time-series
data, supplemented by overlaid line graphs of 3-, 5- and 10-year moving
averages.  His goal was to show that while the initial series
showed wide variability, moving averages made the series progressively
smoother.
</p>


<h3>Usage</h3>

<pre>data(Bowley)</pre>


<h3>Format</h3>


<p>A data frame with 45 observations on the following 2 variables.
</p>

<dl>
<dt><code>Year</code></dt><dd><p>Year, from 1855-1899</p>
</dd>
<dt><code>Value</code></dt><dd><p>total value of British and Irish exports (millions of Pounds)</p>
</dd>
</dl>



<h3>Source</h3>


<p>Bowley, A. L. (1901). <EM>Elements of Statistics</EM>. London: P. S. King and Son,
p. 151-154.
</p>
<p>Digitized from Bowley's graph.
</p>


<h3>Examples</h3>

<pre>
data(Bowley)

# plot the data 
with(Bowley,plot(Year, Value, type='b', 
	ylab="Value of British and Irish Exports",
	main="Bowley's example of the method of smoothing curves"))

# find moving averages-- use center alignment (requires width=ODD)
require(gtools, warn.conflicts=FALSE)
mav3&lt;-running(Bowley$Value, width=3, align="center")
mav5&lt;-running(Bowley$Value, width=5, align="center")
mav9&lt;-running(Bowley$Value, width=9, align="center")
lines(Bowley$Year[2:44], mav3, col='blue', lty=2)
lines(Bowley$Year[3:43], mav5, col='green3', lty=3)
lines(Bowley$Year[5:41], mav9, col='brown', lty=4)

# add lowess smooth
lines(lowess(Bowley), col='red', lwd=2)

require(ggplot2, warn.conflicts=FALSE)
qplot(Year,Value, data=Bowley)+geom_smooth()
</pre>


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